Looking for the proper way to remove the cab air bags from the bottom of the cab. I have them out of the base (held in by round retainer rings) but unsure if they bolt or twist onto a stud on bottom of cab. Also is there a steel spacer that goes between the bags at the top and base? I ask because there was a large piece of rust scale with a hole in the center that came up off the base of the bag and crumbled apart. Any help is appreciated, thank you!